Thestackdata structure can come in handy here in representing this recursive structure of the problem. We can't really process this from the inside out because we don't have an idea about the overall structure. But, the stack can help up process this recursively i.e. from outside to inwar...
For"(()", the longest valid parentheses substring is"()", which has length = 2. Another example is")()())", where the longest valid parentheses substring is"()()", which has length = 4. Another string matching problem, this time I finish this problem in 30 minutes! and got ACCEPT...
My Solutions to Leetcode problems. All solutions support C++ language, some support Java and Python. Multiple solutions will be given by most problems. Enjoy:) 我的Leetcode解答。所有的问题都支持C++语言,一部分问题支持Java语言。近乎所有问题都会提供多个算
LeetCode 中关于括号的题目还是比较多的,比如 Valid Parentheses,Valid Parenthesis String,Remove Invalid Parentheses,和 Longest Valid Parentheses 等。大多都是考察如何判断一个括号字符串是否合法,所谓的合法,大致就是左右括号个数要相同,每个右括号前面必须要有对应的左括号,一个比较简单的判断方法就是用一个变量 ...
https://leetcode.com/problems/longest-valid-parentheses/description/ 来回做了好几遍,虽然AC 了但是这个解发肯定不是最优的。思路是把问题分两步解决:1. 把字符串转换成一个匹配括号的id 序列,比如第0 个和第3 个匹配了,则把0,3都记录在一个数组里。2. 排序生成的这个数组,然后遍历一次找最长的连续串...